Health Risk Assessment of Metals in Surface Water from Freshwater Source Lakes,Pakistan

This study investigated the concentrations of selected metals (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr, and Zn) in freshwater source lakes in Pakistan and assessed the preliminary health risks associated with them. Water samples were collected from Khanpur and Simly Lakes and analyzed for the metals using flame atomic absorption spectrophotometry. Major contributions were noted for Ca, K, Mg, and K; however, the measured levels of Cd, Co, Cr, and Pb were many times higher than the permissible national/international guideline values. The risk characterization revealed that hazard quotient (HQ_ing) and hazard index (HI_ing) values exceeded the acceptable limit unity, indicating non-carcinogenic risk to the recipients via oral intake of contaminated water. The carcinogenic risk (CR_ing) via ingestion route for Cd, Cr, and Pb was found much greater than the acceptable limit (10^–6). Overall, Cd, Co, Cr, and Pb were the major contributors to potential adverse health risk to the inhabitants. Multivariate analysis demonstrated anthropogenic intrusions of the metals in both lakes. The study clearly indicated that there was gross contamination of water in both lakes, so special attention should be paid to manage the pollution sources of metals.